You could focus on the relationship between the sparkle and a character who is initially afraid of it. For example, a young girl who sees the sparkle in the forest at night. She thinks it's something evil but as she gets closer, she realizes it has a warm and positive energy. Then, she devotes herself to spreading the light of the sparkle throughout her gloomy village.
One idea could be exploring the backstory of the main character in 'Darkness of Birth'. Maybe they had a difficult childhood that led to their current state. Another idea is to create a different ending for the story, where the characters face different fates. For example, the protagonist could overcome their inner darkness in a more unexpected way.
Perhaps a fanfiction where the tiger of darkness has a human form as well. In this form, it tries to blend into society but still has its primal instincts. The story could be about the internal struggle it faces between its human side and its dark, tiger nature. It could fall in love with a human, and then the conflict would be about whether to reveal its true self or keep it hidden.
One idea could be to cross it with a superhero universe. The Darkness' powers would create an interesting dynamic against heroes like Superman or Batman. For example, the Darkness' ability to manipulate shadows could be a real challenge for heroes who rely on light or technology.
One idea could be exploring the backstory of a minor character in 'into darkness'. For example, a crew member who has a hidden past related to the main antagonist. Another could be a time - travel plot where a character goes back in time to prevent the events that led to the 'darkness' in the story. Maybe also a story about a character who discovers a new power or ability that could change the course of the events in the 'into darkness' universe.
Perhaps a fanfiction about a character who is trapped in a dark and silent dimension. They have to rely on their inner strength and memories to find a way out. This could explore themes of self - discovery and isolation.
You could also write a fanfiction where the Lord of Darkness has to team up with his enemies to face a greater threat. This would be a great opportunity to explore his character in a different light, showing that even he can put aside his enmity when the situation demands it.
One idea could be exploring the backstory of the main character in 'Master of Darkness'. Maybe they had a normal life before becoming the master of darkness, and you could write about the events that led to their transformation. Another idea is to create a new villain who challenges the master of darkness in unexpected ways, adding more conflict to the story.
Well, a great plot could be Twilight Sparkle as an Alicorn going on a journey to discover the origin of Alicorn magic. This could involve her meeting ancient Alicorn spirits and learning secrets about her own powers. Or perhaps she gets caught in a time - loop where she has to repeatedly use her Alicorn powers to break free and figure out what's causing it. It could also be interesting if she has to teach other ponies how to use Alicorn - related magic.
One plot idea could be Twilight Sparkle getting cold feet before the wedding and her friends having to reassure her. Another could be a magical mishap during the ceremony that causes chaos but in the end makes the wedding even more special. Maybe an old enemy tries to disrupt the wedding but Twilight's love for her partner overcomes all obstacles.
A plot could involve the Prince of Darkness in a battle against other supernatural forces. He has to team up with unexpected allies, like a group of young witches who are also trying to protect their world from a greater evil. This would lead to a lot of character development as they learn to work together.